Hole Cleaning Processor

The efficient transport of drilled cuttings from the bit to surface is always a major issue when drilling inclined or horizontal wells. The mathematical model for this program enables the prediction of cuttings transport in highly deviated to horizontal wells taking account of the operating parameters, wellbore geometry, fluid properties and cuttings characteristics.

The theory used for developing the software is based on the analysis of force balance and cuttings bed motion. The program utilizes a three-layer model for cuttings transport comprising three components: a stationary bed of particles of uniform concentration; a moving bed layer in which particle concentration is varied; and a heterogeneous suspension layer on top. The equations for cuttings concentrations for different wellbore sections have been used to calculate cuttings bed formation and to determine whether the bed remains stationary or slides up the hole. The analysis also determines the position of the cuttings bed formed and the height of the cuttings bed layer.

Applications

The software modeling is valid for an eccentric or concentric annulus for Herschel Bulkley fluids, based on the following inputs: